The conversion of Jews to Catholicism during the Holocaust is one of the most controversial aspects of the record of Pope Pius XII during The Holocaust. According to , who wrote about Vatican diplomacy during the Holocaust, "one of the principal concerns of the Vatican, especially in the early days of the war, was those Jews who had converted to Catholicism, the so-called Catholic or Christian non-Aryans". Morley further argues that Pius XII was "primarily, almost exclusively, concerned about baptized Jews". Moreover, Pius XII's purported fear of reprisals against "non-Aryan Catholics" is often cited as a motive for his not speaking out against the Holocaust.